Mapmaker is the the tool from Google Maps where you can add information - much like you can in Open Streetmaps. By looking at the list of countires and regions where this tool is available I can see a pattern - regions with low density of population or available data.
But to be honest - there are areas even in high population density countries like Italy and Germany where Google Maps still lacks. While I hope they will release this tools for those areas as well I will try to make the map of Canada better :)

About Frank Neulichedl

Hi, I'm Frank Neulichedl. Digital Product Designer, Photographer and Chef. I love to create awesome products with great UX, beautiful UI and modern interactions. Follow me on Twitter, see my pictures on Instagram and don't miss out on the free Brand Personality Questionnaire.